Synthesis of ,-Amino Nitriles from Carbonyl Compounds, Amines, and Trimethylsilyl Cyanide: Comparison between Catalyst-Free Conditions and the Presence of Tin Ion-Exchanged Montmorillonite

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 9 2010Jiacheng Wang
Abstract
In the absence of catalysts, the three-component, one-pot synthesis of ,-amino nitriles proceeded using various aldehydes and ketones together with amines and trimethylsilyl cyanide (TMSCN) in high yields under neat conditions at room temperature.
The addition order of the reagents had a significant influence on the yields of the desired ,-amino nitriles.
In contrast, when tin ion-exchanged montmorillonite (Sn-Mont), prepared by the ion-exchange of sodium montmorillonite (Na-Mont) with a tin tetrachloride solution, was used as a catalyst, the reaction rates significantly increased compared with those without catalysts, and the range of the applicable carbonyl compounds was also extended: structurally diverse aromatic, aliphatic and heteroatom-containing carbonyl compounds, including sterically hindered ketones as well as aliphatic and aromatic amines, were converted into the desired ,-amino nitriles in good to excellent yields with short reaction times under mild conditions.
Sn-Mont showed a better catalytic activity than proton or other metal ion-exchanged montmorillonites, supported SnO2 catalysts and the previously reported homogeneous or heterogeneous catalysts.
The recovered catalyst was reused several times without loss of catalytic performance.
Along with the expansion of the interlayer space of Sn-Mont, the strong Brønsted acid and Lewis acid nature of Sn-Mont derived from protons and SnO2 nanoparticles present in the interlayers of Sn-Mont likely played important and cooperative roles in the high catalytic activity.
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EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2010Shiori Hanada
Abstract
Hydrosilanes act as a reagent to cleave the C,O bond of OtBu groups in carbamates, carbonates, esters, and ethers by catalysis of a triruthenium cluster.
The reaction offers a novel deprotection method for OtBu groups under neutral conditions, showing unique selectivities that have never been accomplished with conventional Brønsted or Lewis acidic promoters.
Possible mechanisms for C,O cleavage are discussed on the basis of NMR spectroscopic analysis.
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Highly Shape-Selective, Biomimetic, and Efficient Deprotection of Carbonyl Compounds Masked as Ethylene Acetals or Dioxolanes Produced from 1,2-Ethanediol

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2010Sébastien Belot
Abstract
The purpose of this study is to point out the synthetic utility of a new class of Michael acceptors (nitrodienes and nitroenynes).
The highly enantioselective organocatalytic Michael addition of carbonyl compounds to these functionalized nitroolefins has been carried out in the presence of (S)-diphenylprolinol silyl ether to achieve some interesting building blocks in high selectivities.
The adducts thus obtained can be easily converted by taking advantage of the corresponding unsaturated carbon-carbon bond.
In presence of the double bond, metathesis or electrophilic activation could be carried out whereas in the presence of the triple bond electrophilic activation could be conducted.
We thus focused on a gold-catalyzed cyclization of the bis-homopropargylic alcohol to afford the corresponding substituted tetrahydrofuran.
Then, we also demonstrated that organic and gold catalysts were compatible in a one-pot process.
Indeed, we developed a one-pot enantioselective organocatalytic Michael addition to a nitroenyne followed by a gold-catalyzed acetalization/cyclization to achieve tetrahydrofuranyl ethers in high diastereo- and enantioselectivities with excellent yields.
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ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Zhan-Guo Chen
Abstract
The regio- and stereoselective aminobromination of ,,,-unsaturated carbonyl compounds and simple olefins catalyzed by elementary aluminium powder has been established by using p -toluenesulfonamide (TsNH2) and N -bromosuccinimide (NBS) as the nitrogen/bromine sources.
The reaction was convenient to carry out with a loading of 1,mol% catalyst at room temperature without inert gas protection.
This method provides an easy approach to trans vicinal haloamino derivatives of ,,,-unsaturated carbonyl compounds and simple olefins in high yields (up to 99.8%) and in excellent regio- and stereoselectivities.
The electron-rich and electron-deficient olefins show significant differences in activity to the aminobromination reaction and give the opposite regioselectivities.
Two possible pathways involving separately a bromonium or an aziridinium intermediate have been proposed.
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ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-13 2005Masaharu Nakamura
Abstract
A modular synthesis of ,-arylated carbonyl compounds has been achieved by the combination of an indium-catalyzed regioselective addition of ,-keto esters to conjugated diynes and a palladium-catalyzed benzannulation reaction.
Indium tris(bistriflylamide), In(NTf2)3, was found to be an efficient catalyst for the first addition reaction of ,-keto esters to diynes.
The reaction proceeds with perfect regioselectivity to give conjugated enynes in high yield.
The second palladium-catalyzed benzannulation proceeds in high to excellent yield and with high regioselectivity for a variety of diynes.
This two-step ,-arylation of carbonyl compounds thus proceeds in a catalytic manner without loss of elements in the starting materials.
The reaction may be performed in a single pot without isolation of the product of the first step.
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ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2005Ho Lee
Abstract
Reactions of organogallium reagents generated from propargyl bromides having substituents at the ,-position and gallium in the presence of 5,mol,% of indium with aldehydes and ketones selectively produced homoallenyl alcohols in good to excellent yields.
Treatment of organogallium reagents obtained from propargyl bromide or propargyl bromides having substituents at the ,-position and gallium in the presence of 5,mol,% of indium with carbonyl compounds selectively afforded homopropargyl alcohols.
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Selective Oxidation of Alcohols to Carbonyl Compounds and Carboxylic Acids with Platinum Group Metal Catalysts

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2003Ross Anderson
Abstract
The use of platinum group metal (PGM) catalysts for the selective oxidation of various primary and secondary alcohols under mild conditions is described.
High throughput screening (HTS) techniques have been used to identify trends in catalyst activity and product selectivity.
Using air as oxidant and water as solvent 5% Pt, 1% Bi/C has been identified as an efficient catalyst for the transformation of 2-octanol to 2-octanone and 1-octanol to octanoic acid.
To improve aldehyde selectivity the promotion of Pt/Al2O3 and Ru/C catalysts has been investigated.
The use of H2O2 as oxidant has been demonstrated as a suitable alternative to air.
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,-Alkylation of Carbonyl Compounds by Direct Addition of Alcohols to Enol Acetates,

CHEMINFORM, Issue 42 2010Takahiro Nishimura
Abstract
The title reaction of dienones, dienamides, or a dienoate affords ,-arylated carbonyl compounds with high enantioselectivities by use of the C2 -symmetric tetrafluorobenzobarrelene-derived iridium complex IRB as catalyst.
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CHEMINFORM, Issue 40 2010Heshmatollah Alinezhad
Abstract
The title reaction can also be carried out in THF at 25 °C with comparable yields.
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ChemInform Abstract: Double Michael Addition of Dithiols to Acetylenic Carbonyl Compounds under the Influence of Molecular Sieve and Dimethyl Sulfoxide.

CHEMINFORM, Issue 17 2010Tomoko Kakinuma
Abstract
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals.
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CHEMINFORM, Issue 13 2010Stanislaw Lesniak
Abstract
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals.
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CHEMINFORM, Issue 13 2010Xiaofang Ma
Abstract
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals.
To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option.
The original article is trackable via the "References" option.
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CHEMINFORM, Issue 51 2009Kenichi Nomura
Abstract
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals.
To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option.
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ChemInform Abstract: A New Approach to 3-Hydroxyprolinol Derivatives by Samarium Diiodide-Mediated Reductive Coupling of Chiral Nitrone with Carbonyl Compounds.

CHEMINFORM, Issue 49 2009Shao-Feng Wu
Abstract
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals.
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CHEMINFORM, Issue 48 2009Victorio Cadierno
Abstract
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CHEMINFORM, Issue 46 2009Santosh T. Kadam
Abstract
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals.
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CHEMINFORM, Issue 38 2009Hisao Nemoto
Abstract
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ChemInform Abstract: Alkali Salt of L-Proline as an Efficient and Practical Catalyst for the Cyanosilylation of a Wide Variety of Carbonyl Compounds under Solvent-Free Conditions.

CHEMINFORM, Issue 32 2009Zhi-Liang Shen
Abstract
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals.
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CHEMINFORM, Issue 31 2009Xiao-Qiang Yu
Abstract
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CHEMINFORM, Issue 22 2009Tomohiko Inagaki
Abstract
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals.
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